Alternating current inductor compass



"0a, 16, 1934. R, N 1,976,723

ALTERNATING CURRENT INDUCTOR COMPASS v Filed Dec. 17, 1331 2 Sheets-Sheet l INVENTOR Ross Gwzn av I flaw/'02 A TTORNEY Oct. 16 1934. R GUNN 1,976,723

ALTERNATING CURRENT INDUCTOR COMPASS Filed Dec. 17, 193.1 2 Sheets-Sheet 2 nvvsuron Ross Gurzn ATTORIVEY titre smunmsf'rnuu i that id relates Wm; n. o.

{Grantedundertheoctoi3,l,sn amended April 3d, 1928; 3% 40). (G. 35%) This invention relates to a compass actuated by cts induced by rotating an inductor memher in the earths magnetic field.

It is the object of invention to provide an inductor com having associated with the indoctor mec v; 1. an accurately synchronized indicating device to show the instantaneous course of a craft on which the compass is mounted and simultaneously make known whether the 19 craft is or is not on the desired course, and if not then'to' show the deviation therefrom.

With the above and other objects in view, the invention consists in the construction, combination and arrangement of partsas will be hereinafter more fully described.

Reference is to be had to the accompanying drawings forming a part of this specification in which like reference characters indicate correspondin parts throughout the several views and hi which T Pig. 1 shows diagrammatically one embodiment of my invention; 1

Fig. 2 shows amodiflcation thereof having a diiferent type of inductor mechanism and luminous indicator;

- Fig. 3 is a. schematic representation of an embodiment having an oscillable instead of rotatable inductor; Fig. iisa detail'ofa portionof the form ofmy invention shown in Fig. 3.

It is well known that when a coil is with its axis v'ertical and is rotated 11; the earths etic iield an alternating current is generated m the 0013, the current being a 1;: on: when .tlie plane of the coil is parallel to the magnetic lines and suhtially zero when the plane is at right angles to those lines. 112 an observer en a craft v:; one of these compasses lmows the orientation of the coil with respect to his craft and ohm position of the coil he can detee the course followed by the craft.

in Fig. l the shaft s, adjusting dish 6, and indieating dish 7 are suitably mounted in a frame (not shown) carried by a universal joint to per= t shaft 5 to remain in a vertical position at all es. A motor s is connected to drive short 5 at a constant speed to rotate coil 9, mounted on shalt 5, in the earths magnetic field.

Slip rings is and ii on shaft 5 are connected to W the terminals of coil Brushes 23 i2 con= tact these rings and are resonated to a movable coil 13 suitably isetween the poles oi permanent means A pointer: 15 is sanded by coil 13 to move over scale 16, whereon are marked 0, L, and R, to indicate respectively on,

"left, or right? with respect to the-timed course. cosh complete rotouon ol the coil 9, pointer 15 moves from Q to R to L and back to 0 under the impulse oi the siting current generated in coil ii.

onshaitsisaletocsusetlioresiliently mounted contact points 1'7! to touch and close a circuit through battery 18 and-transformer primary 19. A condenser 20 is connected across the contacts l'l'to prevent injury thereto by the heavy current set up when the circuit is opened. A flash lamp 221 is connected to secondary 22 of the transformer and is positioned to illuminate the scale 18 each time the circuit through contacts V 17 is closed.

Contacts 17 are mounted on a rotatable disk 6'to vary thepart of the cycieofcoil Qatwhich the circuit through the contacts will be'closed. As shown, this adiustment may be effected by a worm 24 on shaft 25 engaged-with suitable gear n,

teeth on the periphery of disk 6. A second worm 2 6 on shaft 25 engages gear teeth on disk '1, on which disk arev marks designating the points of the compass.

It is evident that by turning shaft 25 the disk 6 may be caused to rotate about its support 41 and so move the contacts 17 to'vary the time of closing the circuit therethrough by cam 16. .The change in position of the contacts 1'! is so coor dinated with the rotation of disk 7 that the flash SI of lamp 21 will occur when the pointer 15 is on 0 if the craft is following the course indicated on the disk 7 by the fixed reference mark 27, but if it deviates therefrom the dash will occur when the pointer is between 0 and either L or R, dem pending upon whether the cralt is to left or right of the set course. The magnitude of the displaceneent of the pointer from O at the time oi the dash measures the degree of deviation from the course. no

The form of the invention shown in 2 is similar to that of Fig. 1 except as to the in-= ductor element and the dashing device. In this form; instead of a rotating coil the current is induced by arms 29and so carried by the shaft- 5 with a stationary coil 31 around the portion 33 that connects the arms. The arms and the portion 32 have high magnetic permeability and low liysteritic loss, and as they revolve in the earths magnetic field currents are set up in coil 31 by the changing flux through portion 32, the currents so genersted moving the coil 13 between the poles of magnet is. The letters L, 0, and R are iun'iinous discharge tubes which will glow when a current is passed through them. One 3m each cycle of said generating means, whereby is minis same imary coil of a transtormenmeans including pcintertocloeethecirciutthroughahyoneoi' sa'idindicia and said secondary coiLaprimary coil of said transformer, means operable by said uch able coil connected'to receive current from said means,- a pointer carried by said'coil, a plurality of luminescent indicia, a secondary coil of a 'transiormer, means including said pointer to close the circuit through any one of said indicia, and said secondary coil, aprimary coil 01 said transformer, and means operable by said shaft to send periodic current impulsu through said coil. 1 7. In a navigating instrument, means to generate current by cutting lines of the earths magneticiield, a plurality of directional indicia, indicator means moved continuously adiacent said indicia by said current the displacement or said means from a zero position being definitely'related to the phase angle of said generating means, means to illuminate at a predetermined point in cycle of said generating means that one of said indicia nearest said indicator means and means operating synchronously with said generating means to flash said illuminating means.

8. In a navigating instrument, symbols to indicate on, "left" or "right with respect to a desired course, means to generate current by. cutting lines of the earths magnetic field, indicator means moved adjacent said symbols by said cur- "rent, the displacement of said meansirom a zero position being definitely related to the phase angle of said generating means and means operating synchronously with said generating means to illuminate one c! said symbols at a predetermined point in each cycle of said generating means whereby is indicated the course of a craftan which said instrument is .mounted with reto said desired course.

9. In a navigating instrument, means to gencrate current by cutting thelines o! the earths magnetic field, a plurality of directional indicia; means movable continuously adjacent said indicia by and in synchronism with said generating means bysaid current, and means to cause transitory illumination of said indicia at a predetermined phase position oi' said generating means in indicated the position of said movablemeans with respect to said indicia at the time ot.occu'r-' rence of said phase position.

10. In a navigating instrumentr means to generate current by cutting lines 01' the earth's magnetic field, a plurality of directionalindicia, means movable continuously adjacent, said indicia by said current, and means operatively connected to said generating means and adjustable to illuminate at a predetermined point in each cycle of and means operatively connected to said generphase position or said position of said movable said generating means that one or said indicia nearest said movable means.

11. In a navigating instrument, symbols to indicate on, "leit or "right" with respect to a desired course, means to generate current by cutting lines of the earth's magneticheldmeans movable adjacent said symbols by said current,

ating means to illuminate one of said symbols at a predetermined point. in each cycle ,0! said generating. means, whereby is indicated the course oi a crait on which said instrument is mounted with respect to said desired course. e

12. In a navigating instrument, means to generate current by cutting lines 01' the earth's magnetic held, a plurality of directional indicia, means movable continuously, adjacent said indicia and in synchronismwith said generating means by said current, and means operatively connected to said generating means to cause transitory illumination 0! said indicia at a predetermined phase position 01 said generating means in each cycle or said generating means, whereby is indicated the position of said movable means with respect to said indicia at the time of occurrence 01' said phase position.

13.In'a navigating instrument, means to generate current by cutting lines o! the earth's magnetic field, a plurality of directional indicia. means responsive to said current including a member movable thereby and anindicator-.mov-' able adjacent said'indicia operatively connected to said movable membe and means operatively connected to said generating means adjustable to. illuminate at a predetermined point in each cycle ct said generating means that one of said indicia nearest said indicator. 14. In a navigating instrument, symbols to indicate "011, left or right" with respect to adesired course, means to generate current by cutting-lines of the earth's magnetic field. means responsive to said current including a member mov able thereby and an indicator movable adjacent said symbols operatively connected to said movable member and means operatively connected to said generating means to illuminate one of said symbols at a predetermined point in each cycle or said generating means whereby is indi-.- cated the course of a-crait on which said instrument is mounted with respect to said desired 128 cent said indicia operatively connected to said movable means, and means operatively connected to said generating means to cause transitory illumination of said indicia .at a "predetermined 188 generating means in each a cycle generating means, whereby is indicated the means with respect to time oi occurrence of said Ross norm.

said indicia at the phase position. 

